Hierarchical Assets Example

This doc attempts to demonstrate how to construct a simple heirarchical asset, with instances and contextual overrides. We’ll create a simple environment asset composed of smaller subassets. In this case, a living room with a couch, coffee table, and side tables with lamps.

Step 1

>>> from abcview.io import Session
>>> s = Session()
>>> s.add_file("lamp.abc")
>>> s.add_file("sidetable.abc")

Note: this is the same as loading both of these abc files into AbcView

$ abcview lamp.abc sidetable.abc

Translate the lamp scene up on the y-axis and save the session

>>> s.items[0].translate = (0, 2, 0)
>>> s.save("step1.io")

Load the session file into AbcView

_images/step1.png 
$ abcview step1.io

Note: you can also move the lamp on top of the table using the properties widget: (ctrl+shift+p or Widgets->Properties), select the lamp, then double-click the translate value and enter 0, 2, 0 and hit enter.

Step 2

Load an instance of the couch and loveseat assets into a new session, and translate them

>>> s = Session()
>>> s.add_file("couch.abc")
>>> s.add_file("loveseat.abc")
>>> s.items[0].translate = (0, 0, -8)
>>> s.items[0].rotate = (-90, 0, 1, 0)
>>> s.items[1].translate = (-8, 0, 0)
>>> s.items[1].rotate = (-90, 0, 1, 0)
>>> s.save("step2.io")

It should look like this

_images/step2.png

Step 3

Now let’s load two instances of the step1.io compound asset created in Step 1, and give them new names

>>> s = Session()
>>> s.add_file("step1.io")
>>> s.add_file("step1.io")
>>> s.items[0].name = "LAMP1"
>>> s.items[1].name = "LAMP2"
>>> s.save("step3.io")

Loading step3.io into AbcView it should look like this

_images/step3.png

Step 4

Instance the step2.io asset, the step3.io asset and the coffee table asset

>>> s = Session()
>>> s.add_file("step2.io")
>>> s.add_file("step3.io")
>>> s.add_file("coffeetable.abc")

Then change the position of the coffee table

>>> s.items[2].rotate = (90, 0, 1, 0)

Now, let’s move lamps next to the couch in this scene by settings its translate property using contextual overrides, and save the scene

>>> s.items[1].items[0].add_override("translate", (-9.0, 0.0, -8.0))
>>> s.items[1].items[1].add_override("translate", (9.0, 0.0, -8.0))
>>> s.save("step4.io")

You should have a scene that looks like this

_images/step4.png

Step 5

Now go back to the step1.io asset and change the height of the lamp, and it should get updated in any compound assets that reference it

>>> s = Session("step1.io")
>>> s.items[0].scale = (1, 0.7, 1)
>>> s.save()

Re-open the step4.io asset and you should see both lamps are now shorter

_images/step5.png

These are just simple examples, but any property, TRS values or arbitrary attributes, can have a contextual override in referencing session files.